Anti-inflammatory medicaments can be classified into those of steroid and of nonsteroidal type. Steroid anti-inflammatory compounds are still the most effective ones in the treatment of inflammatory diseases and conditions such as: asthma, chronic obstructive pulmonary disease, inflammatory nasal diseases such as allergic rhinitis, nasal polyps, intestinal diseases such as Crohn's disease, colitis, ulcerative colitis, dermatological inflammations such as eczema, psoriasis, allergic dermatitis, neurodermatitis, pruritis, conjunctivitis and rheumatoid arthritis. In addition to excellent potency and effectiveness, medicaments of this type also possess numerous unfavourable side-effects, (e.g. disturbance of carbohydrate metabolism, decreased calcium resorption, decreased excretion of endogenous corticosteroids and disturbance of physiological functions of the pituitary gland, adrenal cortex and thymus. Steroids present on the market are highly effective against inflammatory conditions and processes whereas their systemic side-effects are diminished. Patent applications WO 94/13690; 94/14834; 92/13872 and 92/13873 describe the so-called “soft” steroids or hydrolysable corticosteroids designed for topical application at the inflammation site, whereas their systemic side-effects are diminished due to the hydrolysis in the serum, wherein the active steroid very rapidly hydrolyses into the inactive form. An ideal steroid, however, without unfavourable effects in a long-term and continuous treatment as required for the control of diseases such as asthma or Crohn's disease has yet to be found, so that there are intense efforts on the discovery and development of steroids with improved therapeutic profile.
Macrolide antibiotics accumulate preferentially within different cells of subjects, especially within phagocyte cells such as mononuclear peripheral blood cells, and peritoneal and alveolar macrophages. (Gladue, R. P. et al, Antimicrob. Agents Chemother. 1989, 33, 277-282; Olsen, K. M. et al, Antimicrob. Agents Chemother. 1996, 40, 2582-2585). Inflammatory effects of some macrolides have been described in the literature, although their effects are relatively weak. For example, the anti-inflammatory effect of erythromycin derivatives (J. Antimicrob. Chemother. 1998, 41, 37-46; WO Patent Application No. 00/42055) and azithromycin derivatives has been described (EP Pat. Br. 0283055). Anti-inflammatory effects of some macrolides are also known from in vitro and in vivo studies in experimental animal models such as in zymosan-induced peritonitis in mice (J. Antimicrob. Chemother. 1992, 30, 339-348) and endotoxin-induced neutrophil accumulation in rat trachea (J. Immunol. 1997, 159, 3395-4005). The modulating effect of macrolides upon cytokines such as interleukin 8 (IL-8) (Am. J. Respir. Crit. Care. Med. 1997, 156, 266-271) and interleukin 5 (IL-5) (EP Pat. Br. 0775489 and EP Pat. Br. 771564) is known as well.
HR Patent Application No. 20010018, WO 04/005309, WO 04/005310 and WO 02/005531 herein incorporated by reference in their entireties describe compounds of the form:
wherein M represents a macrolide subunit possessing the property of accumulation in inflammatory cells, A represents an anti-inflammatory subunit which can be steroid or nonsteroidal and L represents a chain linking M and A, and improved therapeutic action of these compounds in the treatment of inflammatory diseases and conditions
The macrolide portion of the conjugate has always one or two sugar moities
Compounds in which the steroid or nonsteroidal subunit are linked to the macrolide subunit, via the macrolide nitrogen having only the aglycone moiety, without sugar substituents either in C/3 or C/5 position, also possessing the earlier mentioned therapeutic action, have hitherto not been described.